Voice over Internet Protocol (IP) (VoIP) mainly refers to a service for transmitting voice over an IP network in the form of data packets. A conventional voice coding scheme usually uses adaptive multi rate (AMR) voice coding. The coding scheme supports eight rates: 12.2 kilobits per second (kb/s), 10 kb/s, 7.95 kb/s, 7.4 kb/s, 6.70 kb/s, 5.90 kb/s, 5.15 kb/s, and 4.75 kb/s, and in addition, it also supports a low-rate (1.80 kb/s) background noise coding mode. To further improve voice coding performance, the 3rd Generation Partnership Project (3GPP) defines a new voice coding mode, an enhanced voice service (EVS). At present, standardization for EVS voice source coding is completed, a transport block of a typical-scenario EVS in an air interface is much smaller than a transport block of the conventional AMR, and use of a resource allocation method in the existing Long Term Evolution (LTE) causes a waste of user spectrum resources.